API 5L Sch40 Seamless Carbon Steel Pipe comparison of four anticorrosion coating technologies

　　API 5L Sch40 Seamless Carbon Steel Pipe with hollow section, a large number of used for conveying fluid pipeline, such as conveying,oil, natural gas,gas, water and some solid material pipeline. 

　　The anti-corrosion of steel pipes is very important. Comparison of the following four steel pipe anti-corrosion processes:

　　1: Due to the use of curtain coating, the coating film sags seriously. Besides, due to the unreasonable design of the roller table and chain, the coating film has two longitudinal and multiple circular scratches. The only merit of this process is that it is heated and dried after coating.

　　2: The coating film has quality defects such as sagging, spiral scratches, and whitening. Especially serious is the case that the thickness of the coating on the spiral scratches is only one-fifth of the specified thickness, and the appearance is very poor. At the same time, the process has hidden dangers of process fire caused by static ignition. In recent years, several fire accidents have occurred, is a threat to safe production. No drying process is another important defect of this process. Due to the many insurmountable and mutually restrictive contradictions in this process. It has become increasingly obsolete and cannot meet the requirements of modern factory automatic coating. It will gradually retreat from the field of steel pipe coating.

　　3: It is a technologically advanced but not very mature process. The advantages of spraying and curing between two rollers are self-evident. However, there are equally insurmountable weaknesses. For example, the pretreatment requirements for the surface of the steel pipe are extremely strict, and if you are not careful, the adhesion will be significantly reduced; UV coatings and equipment are expensive and require high technical management; the coating is brittle and suffers Knocking, it is easy to partly fall off, and it is difficult to recoat. Due to so many problems, the promotion of this process is restricted.

　　4: It is a relatively advanced and relatively mature process developed in recent years. It overcomes the serious sag, scratches, whitening, and fragility of the coating film in other processes. The coating film produced by it has strong adhesion, flexibility, superior anti-rust effect, little sagging, and is beautiful and complete. The process also has the characteristics of simple operation, complete supporting facilities, low technical management requirements, and safety. Due to the perfect technology. It is called “the complete set of steel pipe heating airless spraying technology”